Casement windows are hinged on one vertical edge to a window frame and swing either inward or outward. The closure and locking mechanism is typically located on the vertical edge opposite the hinged edge.
Casement windows have utilized various mechanisms to secure closure, primarily for safety, security, and energy efficiency. There are several problems, however, with current designs and manufacture of casement window locks. First, many casement window locks include a complex set of levers, gears, and pins. These locks are difficult and expensive to make, repair, and replace.
Second, many casement window locks have a restricted range of movement that does not permit the window to fully close and seal shut. This is especially so with casement window locks that are slightly out of alignment with the keeper in the adjacent window pane. This misalignment reduces the energy efficiency of the window and presents a possible security flaw.
Third, the complicated nature of many casement window locks and the requirement of numerous moving parts yield a bulky, unsightly device that detracts from the décor of the window.
Thus, there is a need for a simple, elegant casement window lock that is economical to manufacture, has an extended operating range, and uses a minimum of moving parts.